Question

a two digit number is 3 more than 4 times the sum of its digits .if 18
is added to the member ,its digits are reversed .find the number

Answer 1

Let the number be = xy

10x + y - 3 = 4 (x+y)

10x + y - 3 = 4x + 4y

10x - 4x + y - 4y = 3

6x - 3y = 3

2x - y = 1

y = 2x - 1 ----------(1)

10x + y + 18 = 10y + x

10y - y + x - 10x = 18

9y - 9x = 18

y - x = 2 -------(2)

Putting (1) in equn (2)

(2x - 1) - x = 2

2x - 1 - x = 2

x - 1 = 2

x = 3

Putting value of x in equn 2

y - x = 2

y - 3 = 2

y = 5

our number is 35